AMPScript has a problem with your variable values
First name and
Last Name because of the space they contain.
Generally, try to avoid fields with spaces for this needless error.
If not an option, you can wrap those values in square brackets so they still get interpreted.
The most important thing to be learned here is: Read the error messages, they point you exactly to this problem, you can see at the end of each message how the space cuts the variable name after the first word.
this should work:
Var @Email, @fname, @sname,
Set @Email = Email
Set @fname = [First name]
Set @sname = [Second name]
Also, when referencing those variables, don't use spaces:
%%= v(@fname) =%%
Hope this helps!